4) Place pepper halves in large baking dish, place half a piece of cheese into each half, top with some beef/onion/mushroom mixture, then top with other half of cheese

5) Bake in a 350 degree oven for about 25 minutes until peppers are soft and cheese is melted (you can include a little bit of water in the bottom of the pan to help the peppers soften up while cooking if you like them softer)